分佈元素模型在結合A-F移動硬化法則後，對材料循環潛變行為已具有良好的模擬效果，但對材料長期加載時的循環潛變行為仍無法有效描述。本研究即藉由觀察真實材料之行為反應，進而適當地修改A-F移動硬化法則，以期分佈元素模型可適切地模擬材料長期的循環潛變行為。最後針對1070鋼材進行循環潛變行為之模擬分析，並與文獻上的實驗結果作一比較。模擬結果顯示改良後的DEM對單軸向長期循環潛變行為具有良好的模擬能力。

The Distributed Element Model (DEM) Combining with the A-F non-linear kinematic hardening rule is capable of adequately describing the behavior of cyclic ratcheting of materials. However, it still has the disadvantage of not being able to describe appropriately the long-term behavior of cyclic ratcheting. The objective of this study is to improve the modeling capability of the modified DEM for cyclic ratcheting behavior of long-term . To account for this behavior, we modify the A-F non-linear kinematic hardening rule for long-term behavior of cyclic ratcheting according to experimental observations. In this study, we simulate the behavior of cyclic ratcheting of 1070 steel. According to the simulations, DEM Combining with the modified A-F non-linear kinematic hardening rule is capable of adequately describing the behavior of cyclic uniaxial ratcheting of 1070 steel.

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